Deployment Architecture

A deployment architecture is created by mapping the logical building blocks
of an application (the logical architecture) to a physical computing environment in
a way that meets the quality-of-service requirements specified in the deployment scenario.

The deployment scenario is translated into a deployment architecture, as shown
in the following figure.

Figure 4–3 Translating a Deployment Scenario into a Deployment Architecture

One aspect of this architectural design is sizing the physical environment (determining
the number of computers and estimating their processor power and RAM requirements)
to meet performance, availability, security, and other quality-of-service requirements.
Once the sizing has been completed, you map Java ES components and application
components to the various computers in the physical environment. The resulting deployment
architecture must take into account the capabilities of different computers, characteristics
of system infrastructure services, and restrictions on the total cost of ownership
or total cost of availability.

The larger the number of Java ES components in the deployment scenario,
and the more demanding your quality-of-service requirements, the more demanding your
design is on high-power computers and high network bandwidth. Where hardware is limited
or prohibitively expensive, you might have to assess trade-offs between fixed costs
(hardware) and variable costs (human resource requirements) or between different quality-of-service
requirements, or you might have to increase the sophistication of your design.

The design of a deployment architecture often evolves in an iterative fashion.
As a starting point for deployment design, however, Java Enterprise System is developing a set
of reference deployment architectures.

A reference architecture is based on a specific deployment scenario: a logical
architecture with specific quality-of-service requirements. In the reference architecture,
a software solution is deployed across a specific physical environment in a way that
meets specified quality-of-service requirements. Performance testing at specified
loads is based on the same set of use cases from which the deployment scenario was
developed. Reference architecture documentation is available to Java ES customers
under non-disclosure.

Based on a reference deployment architecture or a combination of reference architectures,
you can design a first approximation of a deployment architecture that meets your
own deployment scenario requirements. You can adjust the reference architectures or
use them as reference points, taking into account the difference between your own
deployment scenario and those upon which the reference architectures are based. In
this way, you can assess the impact of your own sizing, performance, security, availability,
capacity, and serviceability needs.